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Understanding implicit in Scala
I was making my way through the Scala playframework tutorial and I came across this snippet of code which had me puzzled:
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How does the Java 'for each' loop work?
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If strings are immutable in .NET, then why does Substring take O(n) time?
Given that strings are immutable in .NET, I'm wondering why they have been designed such that string.Substring() takes O( substring.Length ) time, instead of O(1) ?
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Simple Digit Recognition OCR in OpenCV-Python
I am trying to implement a "Digit Recognition OCR" in OpenCV-Python (cv2). It is just for learning purposes. I would like to learn both KNearest and SVM features in OpenCV.
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KeepAwake 保持唤醒扩展：防止App被操作系统停用 · App Inventor 2 中文网
.navbar .nav-link .mdi, .navbar .dropdown-item .mdi { margin-right: 6px; opacity: .7; } 创建 Apps 文档 文档首页 内置块参考文档 组件参考文档 拓展参考文档 概念参考文档 IoT 参考文档 技术和其他指...
Are there disadvantages to using a generic varchar(255) for all text-based fields?
I have a contacts table which contains fields such as postcode , first name , last name , town , country , phone number etc, all of which are defined as VARCHAR(255) even though none of these fields will ever come close to having 255 characters. (If you're wondering, it's this way becaus...
How do Python functions handle the types of the parameters that you pass in?
Unless I'm mistaken, creating a function in Python works like this:
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Why do this() and super() have to be the first statement in a constructor?
Java requires that if you call this() or super() in a constructor, it must be the first statement. Why?
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Why do we need virtual functions in C++?
I'm learning C++ and I'm just getting into virtual functions.
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Facebook Graph API v2.0+ - /me/friends returns empty, or only friends who also use my application
I am trying to get my friend name and ids with Graph API v2.0, but data returns empty:
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